子组件 ChildCom.vue :
<template>
<input :value = " modelValue" @ input =" inputHandler" />
</template>
<script>
export default{
    inputHandler(e){
        //向父组件派发自定义事件 update:modelValue
        this. $ emit(" update :modelValue" , e. target. value);
    },
},
};
</script>